This guy lives on an island in Nicaragua and gathers plastic waste on the beach. He puts the plastic into a metal tank that is sealed, and builds a fire under it. The plastic pyrolyzes and the fumes are piped through a few condensers where the liquids are drawn off. Some liquids are like diesel
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I made one of these back in 1970 or so. It was inside of a coffee can using the lid for the speaker. This class A power LED driver works good for making a speaker from an audio output transformer and any sheet of steel, even a coffee can with a steel cover. Strip the
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Its not hard to make a signal tracer from an old AM radio. You need 60 mm of red and black flexible twisted pair, a 0.22 uF, 100V capacitor, a small black alligator clip, a 50 mm length of shrink tubing that will fit over the following probe, and a thin 100 mm long piece
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This morning on CBS Sunday Morning they had an article about a farmer who couldn’t repair his $800,000 John Deere tractor and lost several days of work. There is a growing movement in the US to make laws that require manufacturers to allow their customers to repair the equipment they own. This is a backlash
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This is a YouTube video. This guy did a very good job of building an off-grid solar system. It’s transportable, uses four 100 watt panels, two 12V AGM batteries in parallel, can supply 120VAC pure sine wave at 2000 watts and costs under $1,900. This is an excellent video with plenty of details. He calls
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I’ve been seeing the sprinklers reaching a smaller radius after several years, and brown spots between. I was thinking that it was caused by a clogged pipe. I also had some constantly leaky sprinklers that were causing the grass to become soggy and mushrooms were growing. Then I noticed my water bill was several tens
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This is an adapter to connect a source such as a smartphone stereo headphone output to the input of an MP3 recorder. The view and diagram is looking at the back of the adapter where the plugs are inserted into the jacks. The switch handles are on the far side. The switch on the right
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Comment left 2020 May 29 on YouTube video in the title. This video covers MOSFET, dual gate MOSFET, JFET and BJT tuned preamps (preselectors) for his shortwave crystal radio. “The talk about using 18 volts for the cascode got me thinking about tube designs. When the plates need 100+V, and when the heater to cathode
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The standard ferrite antenna loopstick for a 365 pF tuning capacitor has an inductance of about 230 microhenrys. This in combination with the tuning capacitor tunes across the full AM broadcast band. It’s useful to be able to wind your own inductor so it can be used for an antenna coil, a trap to attenuate
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The beginning isn’t clear about how it looks. First, scroll to end and look at the photo. https://www.randombio.com/capacitor.html
